MODEL 2400E NG and 2400E LP - INDOOR MODEL

Transcription

MODEL 2400E NG and 2400E LP - INDOOR MODEL
http://waterheatertimer.org/Troubleshoot-Bosch-Tankless-water-heater.html
MODEL 2400E NG and 2400E LP - INDOOR MODEL
Temperature Modulated with Electronic Ignition
Suitable for heating potable water only
Not approved for space heating purposes
(Intended for variable flow applications)
2400 E NG - Natural Gas
2400 E LP - Liquefied Petroleum (LP) Gas
6 720 608 263 US (2007.10) JS
Warning: If the information in this manual is not
followed exactly, a fire or explosion may result
causing property damage, personal injury or death.
Do not store or use gasoline or other flammable
vapor and liquids in the vicinity of this or any other
appliance.
Improper installation, adjustment, alteration,
service or maintenance can cause injury or
property damage. Refer to this manual. For
assistance or additional information consult a
qualified installer, service agency or the gas
supplier.
In the Commonwealth of Massachusetts this
product must be installed by a licensed plumber or
gas fitter.
Upon completion of the installation, these
instructions should be handed to the user of the
appliance for future reference.
What to do if you smell gas
• Close gas valve. Open windows.
• Do not try to light any appliance.
• Do not touch any electrical switch; do not use any
phone in your building.
• If you cannot reach your gas supplier, call the fire
department.
• Immediately call your gas supplier from a neighbor’s
phone. Follow the gas supplier’s instructions
• Installation and service must be performed by a
qualified installer, service agency or the gas supplier.
Index
Index
1
W a rning
2
2 .1
2 .2
2 .3
2 .4
2.5
A p p l i a n c e d e ta i l s
F eatures
2 4 0 0 E S pec ific ations (T ec hnic al data)
U npac king the 2 4 0 0 E heater
G eneral rules to follow for s afe operation
Dimensions and Minimum installation clearances
4
4
4
5
6
7
3
3 .1
3 .2
3 .3
3 .4
3 .5
3 .6
3 .6 .1
3 . 6 .2
3 . 6 .3
3 .6 .4
3 . 6 .5
3.6.6
3 . 6 .7
3 .7
3 .8
3 .9
3 .1 0
3 .1 2
I n s ta l l a ti o n i n s tr u c ti o n s
Introduc tion
P roper loc ation for ins talling your heater
H eater plac ement and c learanc es
Mounting ins tallation
C ombus tion air requirements
V enting
V ent material and s pec ific ations
V ent c onnec tions
C ondens ate drain tube requirements
R oom s ealed ins tallation (T win pipe)
V ertic al terminations
Horizontal terminations
E xhaus t vent c onfiguration examples
G as piping & c onnec tions
Meas uring gas pres s ure
W ater c onnec tions
E lec tric al c onnec tions
R ec irc ulation applic ation
8
8
8
8
8
9
11
11
12
13
13
14
15
18
19
21
22
23
23
4
4.1
4 .2
4 .3
4.4
4 .5
4 .6
4 .7
4 .8
O p e r a ti o n i n s tr u c ti o n s
For your safety, read before operating your water heater
P ower
T emperature s elec tion
Use of optional rem ote c ontrol ac c es s ory
O peration
R es et button
P rogram button
L oc ked c ondition
5
5 .1
5 .2
5 .3
5 .4
5 .5
Maintenance a n d s e r vi c e
A nnual maintenanc e
W interizing for s eas onal us e
Mineral s c ale build-up
A djus ting C O 2
C ontrol board diagnos tic s
6
6 .1
6.2
6 .3
6 .4
6 .5
6 .6
6 .7
6 .8
T r o u b l e s h o o ti n g
Introduc tion
Burners do not ignite when hot water is turned on
W ater is too hot
W ater is not hot enough
L ow water flow/pres s ure
H ot water temperature fluc tuates at tap
N ois y burner/heater during operation
E rror c ode diagnos tic s
7
E l e c tr i c a l d i a g r a m
41
8
2 4 0 0 E F u n c ti o n a l s c h e m e
42
9
9 .1
9 .2
9 .3
Interior components diagram and parts list
Interior c omponents
C omponents diagram
P arts lis t
10
P r o te c ti n g th e e n vi r o n m e n t
46
11
Fifteen Year Lim
47
2
2
i te d W a r r a n ty
24
24
24
25
27
27
27
27
27
28
28
28
29
29
32
33
33
33
33
33
34
34
34
36
43
43
44
45
1
Warning
For your safety
Do not store or use gasoline or other flammable,
combustible or corrosive vapors and liquids in the
vicinity of this or any other appliance.
Warning: Carefully plan where you
install the heater. Correct combustion
air supply and flue pipe installation are
very important. If a gas appliance is not
installed correctly, fatal accidents can
result from lack of air, carbon monoxide
poisoning or fire.
Warning: Exhaust gas must be vented
to outside using proper vent material
suitable for category III vent systems
and temperatures up to 480°F. Vent
and combustion air piping must be
sealed gas-tight to prevent possibility of
flue gas spillage, carbon monoxide
emissions and risk of fire, resulting in
severe personal injury or death.
Warning: Place the heater in a location
where water leaks will do NO DAMAGE
to adjacent areas or lower floors.
Warning: Field wiring connections and
electrical grounding must comply with
local codes, or in the absence of local
codes, with the latest edition of the
National Electric Code, ANSI/NFPA 70,
or in Canada, all electrical wiring must
comply with the local codes and the
Canadian Electrical Code, CSA C22.1
Part 1.
Warning: Shock hazard: line voltage is
present. Before servicing the water
heater, unplug power supply cord from
outlet. Failure to do so could result in
severe personal injury or death.
Warning: The heater must be
disconnected from the gas supply
piping system during any pressure
testing of that system at test pressures
equal to or more than 0.5 psig.
6 720 608 263
Warning
FCC:
This device complies with Part 15 of the FCC rules.
Operation is subject to the following two conditions: (1)
This device may not cause harmful interference, and (2)
this device must accept any interference received,
including interference that may cause undesired operation.
Fig. 1
6 720 608 263
3
Appliance details
2
Appliance details
2.1
Features
Parts
• Touch pad interface control
• High power pre-mix compact burner with low NOx
emissions
Capacity
Maximum flow rate: 6.35 GP M (24 l/min) at a 45°F
(25°C) rise.
Maximum output
142,968 Btu/h (41.8 kW)
• Modulating gas valve with constant gas to air ratio
control
Maximum input
• Modulating water valve for improved comfort and
temperature control.
Efficiency in %
175,000 Btu/h (51.2 kW)
Safety
Recovery efficiency 86.5%
• Flame sensor (ionization) rod
Min. Output
• Overheat sensor
31,131 Btu/h (9.1 kW)
• Temperature limiter
Temperature Control
• Fan speed monitoring.
Selection range: 100°F (38°C) - 140°F (60°C)
High quality materials for long working life
Default temperature: 122°F (50°C)
• Copper heat exchanger
Stability: +/- 2°F (+/- 1°C)
• High efficiency Ceramat burner
Gas Requirement
• Compact space saver: mounts on a wall with a
supplied bracket.
Gas connection (inches) - ¾” NPT
• Easily removable one-piece cover.
Inlet gas pressure under operation (with a high hot
water flow rate)*
Features
• Propane: 11” - 14” water column
• LCD Display
• Natural Gas: 5” - 14” water column.
• On/Off and temperature control switches
• Reset button
* To measure gas pressure, see Measuring gas
pressure, chapter 3.8.
• Program key (selectable temperature)
Venting
• Failure codes for easy diagnostics and repair
A condensate trap is integrated into the exhaust flue
gas collar of the heater, the supplied condensate drain
tube MUST be installed to it for proper removal of
condensate from the trap. Ad ditional condensate traps
and drains may be necessary; see chapter 3.6 for
Venting.
• Diagnostic mode for trou bleshooting/informational
purposes
Accessories
• Optional wireless remote control accessory to
remotely set temperature (Part # TSTAT2) .
• Horizontal vent termination kit (Part # AQ3) .
Water
• Hot water connection (inches) - ¾” NPT
• Cold water connection (inches) - ¾” NPT
• Water valve material: Polymer (PPS) (Polypropylene
Sulfid)
i
2.2
BOSCH is constantly improving its
products, therefore specifications are
subject to change without prior notice.
2400 E Specifications (Technical
data)
Approved in US/Canada
• Minimum water flow for activation: 0.8 gallon/minute
(3 l/m)
• Minimum recommended water pressure: 30 PSI
(2.07 bar)
• Connections:
– Bottom of heater
Combustion
• NOx ≤ 55 ppm
• CO ≤ 300 ppm
4
6 720 608 263
Appliance details
• CO2 level set from factory, see chapter 5.4.
Dimensions
• Depth (in): 8 ½” (220 mm)
• Width (in): 15 ¾” (400 mm)
• Height (in): 23 ½” (600 mm)
• Weight: 47 pounds (21 kg).
Gas types
• Exhaust vent adaptor (with 4 screws and gasket
provided)
• Condensate drain tube kit
• Combustion air inlet adaptor (with 3 screws and gasket provided)
• Plastic decal shields for covering front cover screws
and control panel, installer should affix these decals
to the front of the unit after installation is complete.
See Fig. 3
Natural Gas.
LP Gas.
Converting the gas type can only be done by a certified
gas technician with a calibrated CO2 analyzer.
Call Bosch Water Heating for conversion information.
• Installation manual (replacement manuals can be
downloaded at www.boschhotwater.com)
Voltage
Please complete and return the enclosed product
registration card.
120 V AC (50/60 Hz)
6 ft power supply cord
Amperage
Idle - 40 mA
Operation - ≤ 2.5 A
Noise
≤ 50 db (A)
Safety devices
• Flame failure device (ionization flame rod sensor)
• Pressure relief valve (supplied with heater)
• Over heat prevention (temperature limiter).
Water resistant
IP X4 (protection against water drops)
2.3
Unpacking the 2400 E heater
Before installing the unit, be certain you have the
correct heater for your type of Gas - Propane or
Natural Gas. Identification labels are found on the
shipping box, and on the rating plate sticker which is
located on the right side panel of the cover.
• Product registration card
• Energy Guide label.
The 2400 E is not approved or designed for:
• Manufactured (mobile) homes, RV's, boats or any
mobile installation.
• Heating or other recirculating/pumping applications*
• Solar/preheat backup or high temperature booster
use.
* This includes domestic hot water circulator pump loop
systems that may be installed in home hot water system
prior to installing this unit. An approved recirculation
design can be found in chapter 3.9. The use of a small
electric mini-tank water heater (4-6 gallon size) must be
used for this application and designed so the pump will
circulate the hot water in the mini-tank only and through
the building's hot water return loop (timed or
thermostatic controlled operation of the pump is
commonly done). The 2400 E must be plumbed in line
before the mini-tank water heater and supplied with
cold water only. Contact Bosch Water Heating if further
instruction is needed.
To remove front cover
• Loosen the two Philips head screws located on front
panel (beneath plastic decal shields if they are
already attached, see Fig. 3)
• Lift front cover panel upward and remove.
Plastic decals
Fig. 2
A
B
Rating plate sticker
Serial number
Type of gas
The box includes:
• Pressure relief valve (150 psi / 200,000 Btu rating)
• Bracket for wall hanging the heater
6 720 608 263
Fig. 3
Remove front cover
5
Appliance details
2.4
General rules to follow for safe
operation
B 1. You must follow these instructions when you
install your heater. In the United States: The
installation must conform with local codes or, in the
absence of local codes, the National Fuel Gas Code
ANSI Z223.1/NFPA 54.
In Canada: The Installation must conform with CGA
B149.(1,2) INSTALLATION CODES and /or local
installation codes.
B 2. Carefully plan where you install the heater. Correct
combustion air supply and vent pipe installation are
very important. If not installed correctly, fatal
accidents can be caused by lack of air, carbon
monoxide poisoning or fire.
B 11. The heater must not be installed in an unheated
area where temperatures will reach 36°F or lower. If
the heater is left in an area susceptible to such
temperatures, refer to Section 5.4 on Winterizing.
B 12. In areas where water supply has a high mineral
content, a water softener is strongly recommended.
Damage to the water heater resulting from hard
water/scale deposits will not be covered under warranty.
B 13. In areas with warm inlet water (70°F or greater),
increasing flow rate at low flowing fixtures may be
required to prevent outlet temperatures from
exceeding the desired temperature set point.
B 3. When the unit is installed indoors with ROOM
SEALED (twin pipe) combustion air and venting, it is
permitted to be located in bathrooms, bedrooms and
occupied rooms that are normally kept closed. See
chapter 3.6. If the unit will be installed indoors and
use indoor combustion air, the place where you
install the heater must have enough ventilation. The
National Fuel Gas Code and National Fire
Codes do not allow UNSEALED gas fired water
heater installations in bathrooms, bedrooms
or any occupied rooms normally kept closed.
See chapter 3.2 and 3.5.
B 4. You must vent your heater. See section on
VENTING.
B 5. The appliance and its gas connection must be leak
tested before placing the appliance in operation.
The appliance must be isolated from the gas supply
piping system by closing its individual manual gas
shutoff valve (not supplied with heater) during any
pressure testing at pressures in excess of ½ Psig
(3.5 kPa).
B 6. Keep water heater area clear and free from
combustibles and flammable liquids. Do not locate
the heater over any material which might burn.
B 7. Correct gas pressure is critical for the optimum
operation of this heater. Gas piping must be sized to
provide the required pressure at the maximum output
of the heater, while all the other gas appliances are in
operation. Check with your local gas supplier and
see Chapter 3.7 Gas piping and connections.
B 8. Should overheating occur or the gas supply fail to
shut off, turn off the gas supply at the manual gas
shut off valve, on the gas line. Note: manual gas
shutoff valve is not supplied with the heater.
B 9. Do not use this appliance if any part has been
underwater. Immediately call a qualified service
technician to inspect the appliance and to replace
any part of the control system and any gas control
which has been underwater.
B 10. Failure to install heater correctly may lead to
unsafe operation and void the warranty.
6
6 720 608 263
Appliance details
2.5
Dimensions and Minimum installation clearances
Fig. 4
Dimensions
1
2
3
4
5
6
Cover
On/Off switch
Reset button
LCD display
Program button
Temperature buttons
Fig. 5
Minimum clearances
Model 2400 E
TOP (A)
12”
FRONT (B)
1”
BACK
0”
SIDES
1”
FLOOR (C)
12”
Table 1 Minimum clearances
6 720 608 263
7
Installation instructions
3
Installation instructions
3.1
Introduction
Please follow these instructions. Failure to follow
instructions may result in:
B Damage or injury.
B Improper operation.
B Loss of warranty.
If you are unable to perform the tasks required to install
this heater properly, please contact a locally licensed
plumber or gas technician.
Please contact Bosch Water Heating with any
questions.
3.2
Proper location for installing your
heater
Carefully select the location of the water heater. For
your safety and for proper heater operation, you must
provide combustion air to the heater and a proper
exhaust vent system.
Follow the guidelines below:
B 1. Locate the heater where venting, gas and
plumbing connections are feasible and convenient.
3.3
The 2400 E is design certified for installation on a
combustible wall (see 3.4 Mounting installation)
provided the floor covering below the heater is
noncombustible. For installations in an alcove or closet,
maintain the minimum clearances to combustible and
non-combustible materials listed below. See also Fig. 5.
A. Top 12 inches (306 mm)
B. Front 1 inches (25 mm)
C. Back 0 inches
D. Sides 1 inches (25 mm)
E. Bottom 12 inches (306 mm)
Clearances from any exhaust vent pipe are dependent
upon the clearance requirements of the stainless steel
vent pipe manufacturer. Single wall stainless steel
(AL29-4C) vent pipe (vent type rated for Category III
appliances) must be used when exhaust venting this
appliance. See 3.6 Venting.
3.4
Warning:
Flammable
materials,
gasoline, pressurized containers, or any
other items or articles that are potential
fire hazards must NOT be placed on or
adjacent to the heater. The appliance
area must be kept free of all
combustible materials, gasoline and
other flammable vapors and liquids.
Warning: The water heater must be
installed in a conditioned space where
temperatures will not fall below 36F.
8
Mounting installation
Warning: before starting installation:
B 2. The hot water lines should be kept short to save
energy. Centrally locating the water heater is
recommended to keep hot water distribution times
even throughout the structure. It is always best to
have hot water lines insulated.
Warning: The water in this water
heater is cold and always remains cold
except for the times the burners are on.
In the event of power outage during
freezing
temperatures,
it
is
recommended that the heater be
drained.
See chapter 5.5 “Winterizing” for
draining instructions.
Heater placement and clearances
B check that there are no loose parts
inside the appliance
B check the gas type of the heater
matches the gas supply you will be
connecting the heater
B ensure that gas pipe, gas valve, mixer,
fan and burner have no damage and are
properly fitted.
i
Front cover should be removed (see
instructions on page 5) in order to inspect
components visually.
B Secure the wall mounting bracket provided with the
heater to a wall surface.
Warning: Do not install this appliance
on a carpeted wall. The heater must be
mounted on a wall using appropriate
anchoring materials.
If wall is sheathed with plasterboard, it is recommended
that two support boards, either 1”x4” or 1/2" (minimum)
plywood first be attached across a pair of studs. Then
attach the heater’s bracket to the upper support board.
The heater should be kept level on the wall surface. See
Fig. 6.
6 720 608 263
Installation instructions
pitch down towards termination ¼ inch for every foot of
horizontal length.
Single pipe method:
Although it is permissible to draw combustion air from
the inside, it is not the manufacturer’s recommended
installation method. Always install a 3 inch elbow on the
top of the combustion air inlet adaptor to prevent
foreign objects from falling into the unit.
If a single pipe installation is utilized, follow guidelines
below for providing adequate combustion air for the
water heater as well as any other appliances that may
consume air in the space. Always follow local codes if
they are more stringent.
Fig. 6
Mounting the heater
3.5
Combustion air requirements
Warning: In areas where outside
temperatures commonly fall below
36°F, a twin pipe venting system is
required. Failure to do so may result in
cold outside air being drawn across the
heat exchanger causing it to freeze and
burst. This failure is not covered under
the manufacturer’s warranty.
Warning: When installed in an
environment where corrosive chemicals
or dirty air are present, the twin pipe
system is required.
Twin pipe method:
The 2400 E is designed as a sealed combustion
appliance. It is recommended that the combustion air
be provided by a dedicated 3” or 4” pipe to the outside.
The combustion air pipe may be aluminum flex, PVC or
any other rigid or semi rigid sealed 3” or 4” pipe. The
combustion air inlet, whether terminating vertically or
horizontally, must be located in such a manner as to
provide a minimum 3 foot clearance from the exhaust
vent terminator. See Fig. 17 Letter I.
The maximum length of the combustion air inlet is 26
feet with one elbow. Subtract 2.5 feet for additional
elbows. Maximum number of elbows permitted is 3.
Horizontally terminating combustion air pipes must
6 720 608 263
Fig. 7
Single pipe installation
The 2400 E water heater holds cold water in its copper
heat exchanger and water valve when not in use.
Because of this, any cold air that comes through the
unit's vent pipe could freeze and damage these
components. This Installation Manual specifies the
minimum vertical vent pipe and the amount of
combustion air required for this unit. When all
requirements are followed, the unit will operate properly
and safely. However, there may still be a risk of freezing
due to negative draft if the other combustion appliances
in the building are not supplied with sufficient
combustion air. A wood stove or furnace can pull its
combustion air from the heater's vent pipe, allowing the
cold incoming air to freeze the cold water in the heat
exchanger. Supplying more combustion air for all
combustion appliances is the solution. A HVAC
specialist should be consulted to design solutions for
providing more combustion air. Observe the following
guidelines:
Installations in structures that have been tightly
constructed (air infiltration rate of 0.40 ACH or less)
must be provided with combustion air per the National
9
Installation instructions
Fuel Gas Code. Consult a HVAC specialist if your air
infiltration rate is questionable.
The space must have two permanent openings, one
commencing within 12 inches of the top and one
commencing within 12 inches of the bottom of the
enclosure. Each opening must have a minimum free
area of one square inch per:
• 1000 Btu/hr if all air is taken from inside the building
• 2000 Btu/hr if all air is taken from the outside by
horizontal ducts
• 4000 Btu/hr if all air is taken from the outside by
direct openings or vertical ducts.
Or the space must be provided with one permanent
opening or duct that is within 12 inches of the ceiling of
the enclosure. This opening must have a minimum free
area of one square inch per:
• 3000 Btu/hr if all air is taken from the outside by a
direct opening or vertical duct.
Louvers, grills and screens have a blocking effect. If the
effective free area is not known, increase the sizes of
your openings by 300% if your louvers are wood and by
35% if your louvers are metal. Refer to the National Fuel
Gas Code for complete information.
10
6 720 608 263
Installation instructions
3.6
Venting
Danger: Do not combination vent this
appliance with any other appliance.
permitted in the total vent length), or subtract 11/4
feet for every 45° elbow used. Horizontal sections of
vent must pitch upwards from heater ¼" for every foot
of horizontal length, to prevent the pooling of
condensate, and be supported at 4 foot intervals with
overhead hangers. See Table 2.
Warning: Do not reduce the vent
(exhaust and combustion) pipe sizes
and do not common vent with any other
vented appliance or stove.
Warning: Failure to vent the exhaust
gases to the outside with sealed
stainless steel vent pipe (AL29-4C)
may result in dangerous flue gases
filling the space in which it is installed.
Diameter
Minimum
length
Maximum
length
Material
Exhaust Vent
3 or 4
inches
3 feet
26 feet with
1 90°
elbow
Sealed single
wall stainless
steel (AL29-4C)
Intake Vent
3 or 4
inches
1 90° elbow
26 feet with
1 90°
elbow
Sealed
aluminum flex,
PVC or any
other rigid or
semi rigid pipe
Table 2 Venting specifications
Warning: Single wall exhaust pipe
MUST be chased through double wall
Type-B vent when passing through an
unconditioned space.
Warning: The vent system must be
installed by a qualified individual in
accordance with these instructions. If
improperly installed a hazardous
condition such as explosion or carbon
monoxide poisoning could result.
Bosch Water Heating will not be
responsible for improperly installed
appliances.
3.6.1
Minimum exhaust vent size and length
The minimum exhaust vent length is
3 feet.
The use of a 90 degree elbow is
equivalent to 2 ½ ft in vent length.
The use of 45 degree elbow is
equivalent to 1 ¼ ft in vent length.
Fig. 8
Minimum exhaust vent length
Vent material and specifications
Establish vent clearances that comply with the vent
manufacturer's specifications. In all cases follow local
codes.
Note: Listed thimbles or collars are necessary to pass
through wall and ceiling partitions. If the vent system
passes through combustible areas where the vent
clearance requirements cannot be maintained, it is
permissible to chase straight sections of sealed 3 inch
single wall vent through 4 inch (or greater) Type-B vent.
The distance to combustibles using this chase
technique is 1 inch (check local codes).
Warning: Type-B vent must never be
used as the actual exhaust vent system
for the appliance, because it is not gas
tight. This will create a serious health
hazard and void the warranty.
Vent lengths
The appliance should be located as close to the point
of termination as possible. The maximum vent length is
26 feet (8 m) with one 90 degree elbow. Subtract 2½
feet from the total vent length for each additional 90°
elbow used (a maximum of three 90° elbows are
6 720 608 263
Reduce maximum
length 2 ½ ft for
each 90 elbow after
the first one and 1 ¼
ft for each 45 elbow.
Fig. 9
Maximum vent and combustion air lengths
Vent material
The 2400 E requires 3 or 4 inch sealed single wall
stainless steel vent pipe (AL29-4C). Use of any other
vent material will void the manufactures warranty and
11
Installation instructions
may result in a hazardous condition. For specific
questions concerning vent material, specifications,
usage or installation, contact the vent manufacturer
directly.
page 33. Correct the problem and then reset the heater
before operating.
3.6.2
Vent connections
Exhaust vent connection
Vent manufacturer
Contact information
B Attach the flue gas exhaust accessory (8 705 504
137) to the top of the unit (position 1) using the 4
screws and gasket provided.
Z-flex
www.z-flex.com
800-654-5600
ProTech Industries
www.protechinfo.com
800-766-3473
Heat-Fab
www.heatfab.com
800-772-0739
Table 3 Vent manufacturer contact information
Z flex
ProTech
Heat Fab
B Insert single wall stainless steel vent pipe into the
exhaust vent adapter 1.5” and tighten the clamp ( Fig.
10 position 2).
Note: 3 to 4 inch increaser required when using 4 inch
pipe.
Note: Failure to fully insert vent pipe and tighten clamp
may cause flue gas leakage or condensate damage that
is not covered under the manufacturer's warranty.
3” Venting
3” Horizontal
termination
2SVSTB03
FSTB3
9390 TEE
3” Vertical
termination
2SVSRCF03
FSRC3
5300CI
90°
Condensate
Drain Tee
2SVEVWCF03
FST3 &
FSDF3
93PPLSTEE
Horizontal
Condensate
Drain
2SVEDWCF03
FSHDT3
9321
Vertical
Condensate
Drain
2SVSEVDP03
N/A
N/A
Condensate
Drain Tube
2SVEDTK
N/A
7000TUBE
Fig. 10 Exhaust vent connection
Combustion air inlet connection
4” Venting
3” to 4”
Increaser
(Required)
2SVI0304
FS0304TI
9374
4” Horizontal
termination
2SVSRTF04
FSTB4
9490TEE
4” Vertical
termination
2SVSRCF04
FSRC4
5400CI
90°
Condensate
Drain Tee
2SVEVWCF04
FST4 &
FSDF4
9416 &
9417D
Horizontal
Condensate
Drain
2SVEDWCF04
FSHDT4
9421
Vertical
Condensate
Drain
2SVEVDP04
FSUCD4
N/A
Condensate
Drain Tube
2SVEDTK
N/A
7000TUBE
The combustion air inlet accessory can be connected
either to the top right or left of the appliance. The
unused side must be sealed.
B Attach the combustion air inlet accessory (8 705
504 115) to the top of the unit (position 3) using the
3 screws and gasket provided.
B Install combustion air pipe over the air inlet accessory. If using flexible piping, secure with a clamp
(position 4, not included).
Table 4 Approved vent termination and condensate
drain part numbers (subject to change)
Vent Safety System
The 2400 E will shut down if inadequate exhaust
venting is detected or a lack of combustion air is
provided to the unit. See troubleshooting section on
12
Fig. 11 Combustion air inlet connection
6 720 608 263
Installation instructions
3.6.3
Condensate drain tube requirements
Exhaust collar condensate drain installation
(supplied with heater)
B The condensate drain tube kit must be used for all
installation types. Failure to properly install
condensate drain will void the warranty.
B When installing the condensate drain tube kit on the
exhaust collar (see diagram below), be sure to form a
trap by means of a 3" (76.2 mm) loop partially filled
with water. This loop must be as low as possible to
allow proper drainage of condensate. The supplied
tube is 3/8" ID high temperature silicone and must be
attached to the condensate port on the exhaust collar
with its supplied gear clamp (first remove brass
screw from port).
B To increase tube length, connect vinyl tubing (not
supplied with heater) to the supplied tube. Do not
reduce tubing diameter when using connector or
additional tubing.
Note: Condensate must be disposed of according to
local codes.
Note: Do not install condensate drain in areas where it
may freeze.
1. Install condensate drain as close to heater as
possible.
2. Use 3/8" ID high temperature silicone tubing to
connect to condensate drain port. Do not use copper
piping for any portion of the condensate drain.
3. Form a condensate trap by means of a 3" loop and
fill bottom of loop with water.
4. To increase the tube length, connect to end of the
high temperature silicone tubing with vinyl tubing,
PVC or CPVC pipe. Do not reduce the internal
diameter at any point.
5. Dispose of condensate according to local codes.
B The condensate must be disposed of according to
local regulations.
Condensate port on exhaust collar
1. Remove brass hex head
screw
2. Fit tube with
gear clamp
3. Loop size and location. Coil tube into 3” loop
with nylon tie (don't crimp tubing) and fill bottom
of loop with water
Fig. 12 Exhaust collar condensate drain installation
Note: No part of supplied silicone tube should be
installed above condensate tapping or improper drainage may occur. (see Fig. 12).
External condensate drain installation (not
supplied)
An additional external condensate drain must be
installed under the following conditions:
• Vertical terminating vent installations
• Horizontal terminating vent installations where the
total vent length is greater than 5 feet
• Vent installation where any section of the exhaust
vent pipe passes through an unconditioned space.
6 720 608 263
Fig. 13 Required condensate drain installation
(Combustion air piping not shown)
3.6.4
Room sealed installation (Twin pipe)
Warning: In areas where outdoor
temperatures commonly fall below
36°F, a twin pipe venting system is
required. Failure to do so may result in
cold outside air being drawn across the
heat exchanger causing it to freeze and
burst. This failure is not covered under
the manufacturer's warranty.
B Although it is permitted to draw combustion air from
inside the structure in warm climates, the recommended method is to provide combustion air through
13
Installation instructions
a 3" or 4" pipe from the outside. See Chapter 3.5 for
more direction on combustion air.
B To reduce pressure differentials between the exhaust
and combustion air intake, it is recommended that
both terminators exit on the same plane. See Fig. 14
for an example horizontal twin pipe termination and
Fig. 15 for the vertical twin pipe termination example.
B Use of two 90° elbows (candy-cane) is an acceptable termination for combustion air intake from the
roof. See Fig. 15 for an example.
B Screening (no smaller than 1/4" mesh) is recommended on candy cane termination.
B Exhaust should terminate above and must be a minimum of 3 feet from must intake termination.
B The exhaust vent must terminate above the roof surface with an approved vent cap not less than 3 feet
(0.6 m) above the highest point where it passes
through the roof and at least 2 feet (0.6 m) higher
than any vertical wall or similar obstruction within 10
feet (3.1m). See Fig. 16 and Table 5.
Fig. 14 Horizontal twin pipe termination
Fig. 16 Vertical
vent
terminations
clearances
(Combustion air piping not shown)
GAS VENT TERMINATIONS FOR LISTED VENT
CAPS
Roof pitch
H (min.)
feet
meters
Flat to 6/12
1.0
0.30
6/12 to 7/12
1.25
0.38
Over 7/12 to 8/12
1.5
0.46
Over 8/12 to 9/12
2.0
0.61
Over 9/12 to 10/12
2.5
0.76
Over 10/12 to 11/12
3.25
0.99
Over 11/12 to 12/12
4.0
1.22
Horizontal runs
Over 12/12 to 14/12
5.0
1.52
Any gas vent section that is greater than 45 degrees
from the vertical is considered horizontal. Horizontal
sections must slope upwards from heater at least ¼
inch for every foot of its horizontal length and be properly supported to allow condensate to be collected by
condensate drains.
Over 14/12 to 16/12
6.0
1.83
Over 16/12 to 18/12
7.0
2.13
Over 18/12 to 20/12
7.5
2.27
Over 20/12 to 21/12
8.0
2.44
Fig. 15 Vertical twin pipe termination
3.6.5
Vertical terminations
Warning: Failure to install a
condensate drain may result in damage
not covered by the manufacturer's
warranty. See chapter 3.6.3.
An approved vent terminator must be
used. See Table 5 for known approved
vertical vent terminations.
Vent terminations
Table 5 Termination heights at various roof pitches
B No pipe joints other than the termination connections
should be exposed to the outdoors. See vent manufacturer instructions for details.
Interior masonry chimneys
14
The single wall stainless steel exhaust vent pipe must
be permanently mounted inside the masonry chimney.
6 720 608 263
Installation instructions
The masonry chimney may have to be tile or metal lined
before the insertion of the gas vent pipe; check local
codes for clarification. You may not vent any other fuel
burning appliances into any free space remaining in the
chimney. The vent terminator must extend at least 3 feet
(0.9 m) above where the chimney meets the roofline and
at least 2 feet (0.6 m) higher than any vertical wall or
similar obstruction within 10 feet (3.1 m). The top of the
chimney must be sealed to prevent rain water or other
elements from entering the chimney.
Exterior masonry chimneys
Refer to the National Fuel Gas Code and consult a local
venting HVAC contractor. Not recommended in cold
climates.
3.6.6
Horizontal terminations
• For horizontal vent runs less than 5 linear feet, the
entire vent run must pitch down to termination 1/4"
per foot to eliminate the danger of rain from entering
the venting system.
• The exhaust vent must terminate immediately once it
penetrates the outside wall.
• An approved vent terminator must be used. See
Table 4 for known approved horizontal vent
terminations.
• Install an additional condensate drain (not supplied)
if the total straight vent length is greater than 5 feet
or if the exhaust vent pipe passes through an
unconditioned space.
• Terminating the intake air piping above the exhaust
termination is not recommended.
• Fig. 17 and table 6 show the required clearances for
the vent termination. Follow local codes if more
stringent.
3.6.6.1 Attention residents of the Commonwealth
of Massachusetts:
In the Commonwealth of Massachusetts the following
regulation went into effect on 12/30/2005:
(a)For all side wall horizontally vented gas fueled equipment installed in every dwelling, building or structure
used in whole or in part for residential purposes, including those owned or operated by the Commonwealth
and where the side wall exhaust vent termination is less
than seven (7) feet above finished grade in the area of
the venting, including but not limited to decks and
porches, the following requirements shall be satisfied:
1. INSTALLATION OF CARBON MONOXIDE DETECTORS. At the time of installation of the side wall horizontal vented gas fueled equipment, the installing
plumber or gasfitter shall observe that a hard wired
carbon monoxide detector with an alarm and battery
back-up is installed on the floor level where the gas
equipment is to be installed. In addition, the installing
plumber or gasfitter shall observe that a battery operated or hard wired carbon monoxide detector with an
6 720 608 263
alarm is installed on each additional level of the dwelling, building or structure served by the side wall horizontal vented gas fueled equipment. It shall be the
responsibility of the property owner to secure the
services of qualified licensed professionals for the
installation of hard wired carbon monoxide detectors.
a. In the event that the side wall horizontally vented
gas fueled equipment is installed in a crawl space or
an at tic, the hard wired carbon monoxide detector
with alarm and battery back-up may be installed on
the next adjacent floor level.
b. In the event that the requirements of this subdivision can not be met at the time of completion of
installation, the owner shall have a period of thirty
(30) days to comply with the above requirements;
provided, however, that during said thirty (30) day
period, a battery operated carbon monoxide detector
with an alarm shall be installed.
2. APPROVED CARBON MONOXIDE DETECTORS.
Each carbon monoxide detector as required in
accordance with the above provisions shall comply
with NFPA 720 and be ANSI/UL 2034 listed and IAS
certified.
3. SIGNAGE. A metal or plastic identification plate shall
be permanently mounted to the exterior of the building at a minimum height of eight (8) feet above grade
directly in line with the exhaust vent terminal for the
horizontally vented gas fueled heating appliance or
equipment. The sign shall read, in print size no less
than one half (1/2) inch in size, "GAS VENT
DIRECTLY BELOW. KEEP CLEAR OF ALL
OBSTRUCTIONS".
4. INSPECTION. The state or local gas inspector of the
side wall horizontally vented gas fueled equipment
shall not approve the installation unless, upon
inspection, the inspector observes carbon monoxide
detectors and signage installed in accordance with
the provisions of 248 CMR 5.08(2)(a)1 through
4.
(b) EXEMPTIONS: The following equipment is
exempt from 248 CMR 5.08(2)(a)1 through
4:
1.The equipment listed in Chapter 10 entitled
"Equipment Not Required To Be Vented" in the most
current edition of NFPA 54 as adopted by the Board;
and
2. Product approved side wall horizontally vented
gas fueled equipment installed in a room or structure
separate from the dwelling, building or structure
used in whole or in part for residential purposes.
(c) MANUFACTURERS REQUIREMENTS - GAS
EQUIPMENT VENTING SYSTEM REQUIRED.
When the manufacturer of Product Approved side
wall horizontally mounted gas equipment provides a
venting system design or venting system components with the equipment, the instructions provided
by the manufacturer for the installation of the equipment and the venting shall include:
15
Installation instructions
1. Detailed instructions for the installation of the venting system or the venting system components: and
2. A complete parts list for the venting system design
or venting system.
(d) MANUFACTURER REQUIREMENTS - GAS
EQUIPMENT VENTING SYSTEM NOT PROVIDED.
When the manufacturer of a product approved side
wall horizontally vented gas fueled equipment does
not provide the parts for the venting of flue gases, but
identifies "special venting systems," the following
requirements shall be satisfied by the manufacturer:
1. The referenced "special venting system" instructions shall be included with the appliance or equipment installation instructions; and
2. The "special venting systems" shall be product
approved by the Board, and the instructions for that
system shall include a parts list and detailed installation instructions.
(e) A copy of all installation instructions for all products approved side wall horizontally vented gas
fueled equipment, all venting instructions, all parts
lists for venting instructions, and/or all venting design
instructions shall remain with the appliance or equipment at the completion of the installation.
16
6 720 608 263
Installation instructions
Recommended exhaust vent terminator clearances
Fig. 17
Ref.
Description
A
Directly below an opening; operable windows, doors and any nonmechanical fresh air openings
Minimum distance
36 in (twin pipe installation)
48 in (single pipe installation)
Below a gutter, sanitary pipework or eaves
24 in
B
Below a gutter, sanitary pipework or eaves, protected by metal
shielding
12 in
C
From any internal corner
12 in
Above ground or snow pack
12 in
D*
Above a paved sidewalk
E
From an opposing wall or structure facing the termination
7 ft
24 in
From the relief valve of a gas regulator
36 in
F
From a terminator facing a terminator
48 in
G
Vertically between two exhaust vent terminators on the same wall
60 in
H
Horizontally between two exhaust vent terminators on the same wall
12 in
Horizontally and vertically from combustion air inlet of a twin pipe
system
36 in
From the gravity combustion air inlet any other equipment
48 in
J
From any external corner
12 in
K
Horizontally from an opening; operable windows, doors and any nonmechanical fresh air openings
12 in (twin pipe installation)
48 in (single pipe installation)
L
Vertically from a wall, roof slope, or obstruction (venting through a flat
or pitched roof)
see Chapter 3.6.5
I**
Table 6
* Subject to local codes and anticipated snow level
** Other equipment that operates with a mechanical air inlet may require greater distances, reference manufacturer's instructions
NOTE: terminating exhaust vent under a deck is not recommended
6 720 608 263
17
Installation instructions
3.6.7
Exhaust vent configuration examples
Supporting the exhaust vent system
Fig. 18 Horizontal side wall venting installation
(combustion air piping not shown)
Note: Pitch venting up 1/4" per foot to termination and
add additional condensate drain for vent runs longer
than 5 linear feet.
Note: Pitch venting down 1/4" per foot to termination
for vent runs less than 5 linear feet.
Note: For horizontal terminations, venting must
terminate once it penetrates to the outside of the
structure. There should be no sections of vent pipe
exposed to the outdoors.
Fig. 20 Vertical venting installation - Interior masonry
Chimney (combustion air piping not shown)
Fig. 19 Vertical venting installation (combustion air
piping not shown)
18
6 720 608 263
Installation instructions
3.7
Gas piping & connections
Before connecting the gas supply, check the rating
plate on the right side of the heater to be sure that the
heater is rated for the same gas to which it will be
connected.
In the United States: The installation must conform with
local codes or, in the absence of local codes, the
National Fuel Gas Code ANSI Z223.1/NFPA 54.
In Canada: The Installation must conform to CGA B149
INSTALLATION CODES and/or local installation
codes.
manufacturer’s sizing tables to determine the pipe
diameter necessary to accommodate the 175,000 BTU
demand of the heater. If there are more gas drawing
appliances on the line, size the gas line according to the
total maximum amount of BTU draw for all appliances.
Note: Under sizing the gas line may result in diminished
output and improper operation. See chapter 3.8 for the
procedure to confirm gas pressure. Proper gas
pressure must be confirmed at time of installation.
Warning: DO NOT connect to an
unregulated or high pressure propane
line or to a high pressure commercial
natural gas line.
Warning: The heater must be isolated
from the gas supply piping system
during any pressure testing of that
system at test pressures equal to or
more than 0.5 psig. If overpressure has
occurred, such as through improper
testing of the gas lines or malfunction of
the supply system, the gas valve must
be checked for safe operation.
Inlet gas particle screen
Gas piping
Fig. 21
GAS CONNECTIONS
B Install a manual gas shut off valve on the gas supply
line.
B Install a union when connecting gas supply.
B The minimum diameter required for any appliance
connector used is ¾” ID.
B National Fuel Gas Code requires that a sediment
trap (drip leg) be installed on gas appliances not so
equipped. The drip leg must be accessible and not
subject to freezing conditions. Install in accordance
with the recommendations of the serving gas
supplier.
Once connections are made, check for gas leaks at all
joints. Apply some gas leak detection solution to all gas
fittings. Bubbles are a sign of a leak. A combustible gas
detector may also be used to detect for leaks.
Danger: If you have a leak, shut off the
gas. Tighten appropriate fittings to stop
leak. Turn the gas on and check again
with a gas leak detection solution.
Never test for gas leaks using a match
or flame.
GAS LINE SIZING
The gas supply piping should be sized for a maximum
draw of 175,000 BTUH. Measure the length of gas
supply line and use the tables in Fig. 22 or the gas line
6 720 608 263
19
Installation instructions
FOR NATURAL GAS
Maximum Capacity of pipe in Cubic Feet of Gas per Hour for Gas Pressure of 0.5 Psig or less and a Pressure drop
of 0.3” in Water Column (0.75mbar).(Based on a 0.60 Specific Gravity Gas) Btu numbers given in thousands.
Follow boxed numbers for piping just one 2400 E (example: ¾” B.I. Natural Gas pipe for 20 ft (6.1m). will
handle 190,000 btu’s (55.7 kWh). For multiple appliances combine the total btu input load and then refer to
applicable chart below.
Nominal
Iron
Length of Black Iron Pipe, Feet
Pipe
Internal
Size,
Diameter
inches inches
10
20
30
40
50
60
70
80
90
100
125
150
175
200
1/4
0.364
32
22
18
15
14
12
11
11
10
9
8
8
7
6
3/8
0.493
72
49
40
34
30
27
25
23
22
21
18
17
15
14
1/2
0.622
132
92
73
63
56
50
46
43
40
38
34
31
28
26
3/4
0.824
278
190
152
130
115
105
96
90
84
79
72
64
59
55
1
1.049
520
350
285
245
215
195
180
170
160
150
130
120
110
100
1 1/4
1.380
1050
730
590
500
440
400
370
350
320
305
275
250
225
210
1 1/2
1.610
1600
1100
890
760
670
610
560
530
490
460
410
380
350
320
2
2.067
3050
2100
1650
1450
1270 1150 1050
990
930
870
780
710
650
610
Length of Flexible Corrugated Stainless Steel Tubing (CSST), Feet
Tube
size,
inches
1/2
EHD*
10
20
30
40
50
60
18 EHD 82
58
47
41
37
34
3/4
23 EHD 161
116
96
83
75
68
1
30 EHD 330
231
188
162
144
131
1 1/4
37 EHD 639
456
374
325
292
267
* EHD = Equivalent Hydraulic Diameter. The greater the
value of EHD, the greater the gas capacity of the tubing.
FOR LP GAS
Maximum Capacity of Pipe in Thousands of BTU per Hour of Undiluted Petroleum Gases (at 11 inches Water Column Inlet
Pressure) (Based on a Pressure Drop of 0.5 Inch Water Column).
* EHD = Equivalent Hydraulic Diameter. The greater the
value of EHD, the greater the gas capacity of the tubing.
Length of Flexible Corrugated Stainless Steel Tubing (CSST), Feet
Nominal
Tube
size
inches
Black Iron Pipe
iron
Length of Pipe, Feet
pipe
10
Inches
20
30
40
50
60
80
100
125
150
EHD*
10
200
20
30
40
50
60
1/2
291
200 160 137 122 110 94
84
74
67
58
1/2
18 EHD 129
91
74
64
58
53
3/4
608
418 336 287 255 231 197
175
155
140
120
3/4
23 EHD 254
183
151
131
118
107
1
1145 787 632 541 480 434 372
330
292
265
227
1
30 EHD 521
365
297
256
227
207
1 1/4
37 EHD 971
661
528
449
397
359
Maximum
Capacity
of
Semi-Rigid
(flexible,
non
corrugated) Tubing in Thousands of BTU per Hour of
Undiluted Liquefied Petroleum Gases (at 11 inches
Water Column Inlet Pressure).
Copper
Length of Tubing, Feet
Outside
diameter
Inch
10
20
30
40
50
60
70
80
90 100
3/8
39
26
21
19
_
_
_
_
_
_
(Based on a Pressure Drop of 0.5 Inch Water Column)
1/2
92
62
50
41
37
35
31
29
27
26
* Source National Fuel Gas Code NFPA 54, ANSI
Z223.1 - No Additional Allowance is necessary for an
ordinary number of fittings
5/8
199 131
107
90
79
72
67
62
59
55
3/4
329 216
181 145
131
121 112 104
95
90
Fig. 22
20
6 720 608 263
Installation instructions
3.8
Measuring gas pressure
Confirm proper gas pressure upon installation.
Connecting Manometer
B Shut off gas supply at installer supplied shutoff valve.
B Remove front cover and locate inlet gas pressure
measuring point (see Fig. 24).
B Loosen screw inside left test point fitting (do not
remove) and connect manometer tube to test point.
Remove screw completely if correct size adapter is
available.
Static Pressure Test
Fig. 24 Gas pressure measuring (left tapping)
Static Gas Pressure Reading (see Chapter 3.8)
enter here: ___________________ Date: ___________
B Turn gas supply back on.
B Operate all other gas appliances (except heater) on
same gas piping system at maximum output.
B Record static gas pressure reading in table 7.
Operating Pressure Test
Operating Gas Pressure Reading (see Chapter 3.8)
enter here: ___________________ Date: ___________
Table 7
HIGH ALTITUDE OPERATION
B ON/OFF switch in position OFF (0).
B Press and hold "Program" (P) button and turn ON/
OFF switch to ON position.
Natural
Gas:
Liquid
Propane:
0 - 4,000 ft
(0 - 1,219 m)
no
modification
no
modification
4,000 ft - 7,000 ft
(1,219 m - 2,134 m)
CO2 adjustment with flue
gas analyzer required See
section 5.4 for instructions.
Above 7,000 ft
(above 2,134 m)
Fig. 23
B As soon as '188' is displayed, release "Program"
, button and the display should read P2.
B Press
Altitude
For operation at
elevations
above 2,000 ft
(610 m) the
equipment
ratings shall be
reduced at the
rate of 4% for
each 1,000 ft
(305 m) above
sea level
Not approved
Table 8
until P1 appears.
Note: While in this mode the appliance will run
constantly at maximum power and allow maximum water
flow.
B Turn on a high volume of hot water (at least 4 gpm)
and heater will ignite. If heater display reverts to P2,
open more hot water fixtures to allow sufficient flow.
Press
until P1 reappears on display.
B Record lowest operating gas pressure reading in
table 7.
Gas pressures lower than 5" W.C. for Natural Gas or
11" W.C. for LPG will result in insufficient degree rise
to the hot water being used, possible error code faults
and must be corrected. See Gas Connections,
chapter 3.7.
6 720 608 263
21
Installation instructions
3.9
Water connections
or flush the lines before connecting to the water
heater.
Warning: This heater must be supplied
with cold potable water. It is not
approved
for
preheated
water
applications. See chapter 3.12 for
approved recirculating application.
B Full port shutoff valves should be installed on both
the cold water supply and hot water outlet lines to
facilitate servicing the heater (see Fig. 26).
Warning: In areas where the water
supply has a high mineral content, a
water softener is strongly
recommended. Damage to the water
heater resulting from hard water/scale
deposits will not be covered under
warranty.
Connecting the pressure relief valve (PRV)
B When facing the heater, the ¾” cold inlet connection
is on the bottom right and the hot connection is on
the bottom left. Centrally locating the water heater is
recommended to keep hot water distribution times
even throughout the structure.
Note: If water flow or pressure is low, or heater does
not ignite, check the water inlet filter screen for debris
(see Chapter 5.1).
A listed pressure relief valve supplied with the heater
must be installed at the time of installation. No valve is
to be placed between the PRV and the heater. No
reducing coupling or other restriction may be installed
in the discharge line. The discharge line must be a
minimum of 4” above a drain and installed such that it
allows complete drainage of both the PRV and the line.
The location of the PRV must be readily accessible for
servicing or replacement, and be mounted as close to
the water heater as possible. See Fig. 26. To install the
PRV, a suitable fitting connected to an extension on a
“T” fitting can be sweated to the hot water line.
Support all piping.
INLET
FILTER
UNION
(not supplied with
heater)
HOT
COLD
Fig. 25
B The use of unions when connecting both water pipes
to the cold and hot water connections is required.
This will facilitate any necessary servicing.
Fig. 26 Plumbing connections (with isolation valves)
and pressure relief valve
B Plastic or PEX type plumbing line materials are not
suitable for connecting directly to the water heater.
B Although water piping throughout the building may
be other than copper, we recommend that copper or
suitably rated stainless steel flex line piping be used
for the water connections for 1.5’ on either side of
the water heater (follow local codes if more stringent).
B Never sweat any rigid piping directly to or beneath
the water connections, as damage can occur to the
internal water valve from heating of the pipe.
B Keep water inlet and outlet pipes to no less than ¾"
(19.05mm) diameter to allow the full flow capacity.
B If the cold and hot connections to the heater are
reversed, the heater will not function. Be certain there
are no loose particles or dirt in the piping. Blow out
22
6 720 608 263
Installation instructions
3.10 Electrical connections
2400
E
Warning: For
safety
reasons,
disconnect the power supply cord to
the heater before any service or testing
is performed.
Warning: This heater must be
electrically grounded in accordance
with the most recent edition of the
National Electrical Code NFPA 70. In
Canada, all electrical wiring to the
heater should be in accordance with
local codes and the Canadian Electrical
Code, CSA C22.1 Part 1. Do not rely
on the gas or water piping to ground the
metal parts of the heater.
The 2400 E requires an electrical power supply from a
120VAC / 60Hz circuit (with a dedicated outlet) and
must be properly grounded.
A means for switching of f the 120VAC power supply
must be provided.
The heater is wired as shown in the wiring diagram
(chapter 7, Fig. 44).
3.12 Recirculation application
Since recirculation through the heater is not
permissible, the following drawing is provided to outline
a proper recirculation application using the Aquastar
water heater with an Ariston minitank water heater. This
schematic is for illustration only and must not be used
for actual installation without appropriate engineering
and technical advice from a properly licensed
professional in the locality where the installation is
made.
6 720 608 263
Ariston Minitank
Fig. 27 Recirculation application
1
2
3
4
5
Full port isolation valve
Circulator
Check valve
PRV
Expansion tank
The use of a small electric mini-tank water heater (4-6
gallon size) should be used for this application and
designed so the pump will circulate the water through
the mini-tank and the building's hot water return loop
only. Timed or thermostatically controlled operation of
the pump is commonly done. The 2400 E must be
supplied with cold water only and plumbed in line
before the mini-tank water heater. Contact Bosch
Water Heating if further information is needed.
23
Operation instructions
4
Operation instructions
Fig. 28
1
2
3
4
5
6
4.1
On/Off switch
Reset button
Program “
“ button
Increasing temperature selector
Decreasing temperature selector
LCD display
For your safety, read before operating your water heater
Warning: The front cover of this
appliance must be secured and
properly sealed at all times once vent
pipe and water connections are made.
Failure to do so may result in freezing
(not covered under warranty), improper
fuel air mixture or error code faults.
Warning: If you do not follow these
instructions exactly, a fire or explosion
may result causing property damage,
personal injury or loss of life.
A. This appliance is equipped with electronic ignition for
lighting the main burners. When turning the heater on,
follow these instructions exactly.
B. Before operating the unit, set the On/Off switch to
the On ( I ) position.
B Immediately call your gas supplier from a neighbors
phone. Follow the gas supplier’s instructions.
B If you cannot reach your gas supplier, call the fire
department.
C. Use only your hand to turn the on/off control switch.
Never use tools. Follow these instructions exactly. If
control switch is jammed, close the gas supply and call
Bosch Technical Support. Attempted forceful repair
may result in a fire or explosion.
D. Do not use this appliance if any part has been under
water. Immediately call a qualified service technician to
inspect the appliance and to replace any part of the
control system and any gas control which has been
under water.
4.2
Power
On
B To start the appliance move the on/off switch to the
"on" position (I).
LCD will display the default temperature factory
setting 122°F (50°C).
WHAT TO DO IF YOU SMELL GAS
B Do not try to light any appliance.
B Do not touch any electric switch; do not use any
phone in your building.
Fig. 29
24
6 720 608 263
Operation instructions
Off
B To shut down the appliance move the on/off switch to
the “off” position (0).
4.3
Temperature selection
To select output water temperature:
B Press buttons
temperature.
and
in order to reach desired
Fig. 30
If the outlet water temperature is set too high, the heater
can produce temperatures that are too hot. A
temperature balance shower valve will automatically mix
in cold water to reduce such hot water temperature. In
the event of any temperature fluctuation with the use of
a temperature balance shower valve, refer to shower
valve manufacturer's instructions for internal adjustment
setting. Adjustments should be made to the hottest
setting in the shower valve. Additionally the temperature
control of the heater can be lowered to produce a more
comfortable hot water temperature.
6 720 608 263
25
Operation instructions
Setting the water temperature
The desired temperature of the hot water can be adjusted on the front control panel of the heater.
The 2400 E has an electronically controlled gas valve that modulates the burner input in response to both varying hot
water flow rates and/or changes in any incoming and outgoing water temperatures.
Note: selected temperature on heater’s display will blink until that temperature has been reached.
Fig. 31 Flow/temperature chart
Note: Low flowing fixtures are the leading cause of
temperature overshoot. To combat this symptom, clean
aerators and shower heads or replace with higher
flowing fixtures if necessary.
26
6 720 608 263
Operation instructions
4.4
B press reset button in order to return heater to normal
operation.
Use of optional remote control
accessory
Fig. 35 Reset button
If the problem persists or error code will not reset,
contact your installer.
Fig. 32 Remote control
The wireless remote control accessory and the
temperature selector buttons on the front of the water
heater operate identically. Contact your installer or
distributor to order the remote control accessory.
Modification of the water heaters interior control unit
(Fig. 48, component 25) is required when installing the
remote control with this heater.
i
4.5
4.7
Program button
The program button can be used on the appliance and
on the remote control.
Programming “Program” function
Programming actions are similar for both controls
(appliance control pad and wireless remote control).
NOTE: up to 6 remote controls can be
programmed for one single water heater,
each with a range distance of 98 ft (30 m).
Operation
B When a hot water tap is opened, main burner ignites
and LCD displays indication
.
Fig. 36 “Program”
B Press buttons
memorized.
button
or
B Hold “Program”
temperature.
to select temperature to be
button for 3 seconds to save
When LCD stops blinking, selected temperature has
been memorized.
Fig. 33
B LCD blinks until selected temperature is reached.
If display blinks continously, heater cannot maintain
or achieve selected temperature.
4.6
Reset button
If the LCD displays the error symbol
and error code
do not shut off power or unplug the heater.
Record the error code displayed on LCD and consult
“Troubleshooting” section (Section 6.8, page 36).
Using “Program” function
In order to select memorized temperature
B Press “Program” key.
LCD shows pre-memorized temperature, which is now
the hot water selected temperature.
4.8
Locked condition
This condition is only valid for appliances utilizing one or
more remote controls.
Fig. 37 Locked condition
Fig. 34
After
following
instructions
“Troubleshooting” section:
6 720 608 263
indicated
in
Whenever LCD shows
the temperature setting
cannot be adjusted because the appliance is in use by
a user which already selected a different temperature.
Appliance will be automatically unlocked after closing
hot water tap.
27
Maintenance and service
5
Maintenance and service
Warning: Always turn off the electrical
power supply, turn off the manual gas
valve and turn off the manual water
control valves when servicing heater.
The unit should be checked once a year by a gas
technician. If repairs are needed, the repairs should be
done by a gas technician
5.1
Descaling
• In areas where the water supply has a high mineral
content, the heat exchanger may need to be flushed
with a descaling solution. Scale build up will shorten
the life of the water heater and damage resulting from
scale is not covered under warranty. Refer to
section 5.3 for detailed instructions on descaling the
heat exchanger.
Heat exchanger
Annual maintenance
(To remove front cover, see page 5.)
Venting System
• Venting system - inspect inside of flue pipe for any
blockage or restriction. Observe burner flames
during heater operation. Verify that the damper inside
flue gas exhaust accessory is able to move freely.
(Vent pipe must be removed in order to access
damper). Inspect the combustion air inlet pipe for
blockage or debris. Inspect combustion air and
exhaust terminations for blockage or debris.
Combustion chamber
• Inspect burner observation window (Fig. 46, #10) for
cracks or leakage of flue gases. Observe burner
flames during heater operation. Flames should be
steady and blue with no signs of yellowing. Yellow
burner flames are an indication of improper
combustion. Refer to Section 3.5 & 3.6 of this
manual to verify exhaust system and combustion air
supply meets manufacturer's specifications.
Pressure relief valve
• Inspect heat exchanger fincoil for soot build-up or
blockage. To access fincoil, venting must be
removed from flue gas exhaust accessory. With
venting removed, manually hold open damper and
inspect fincoil below with a flashlight. If there is
evidence of soot build-up or blockage, the heat
exchanger should be removed by a professsional and
cleaned thoroughly. To remove the heat exchanger,
consult
service
bulletin
TWH-G2-22
at
www.boschhotwater.com.
5.2
Winterizing for seasonal use
Please note that installation instructions state that the
water heater must not be installed in a location where it
may be exposed to freezing temperatures. If the heater
must be left in a space which is likely to experience
freezing temperatures (less than 36° F), all water must
be drained from the heater. If precautions are not taken,
resulting damage will not be covered under the
warranty. NOTE: Use of agents such as anti-freeze is
not recommended as they may cause damage to the
water heater's internal components.
• Manually open the pressure relief valve to ensure
proper operation.
1. Turn on/off switch on the water heater to the off (O)
position and unplug power supply cord. The display
should be blank.
Inlet water filter
2. Shut off gas supply to heater.
• Verify the inlet filter screen is clean and undamaged.
The inlet water filter is located within the ¾" cold
water inlet on the bottom right side of the appliance
(See Fig. 38). Close installer supplied cold water
shutoff and remove cold water supply pipe. Remove
filter, clean or replace if damaged.
3. Shut off the water supply to the water heater using
installer supplied shutoff valve.
INLET
FILTER
4. Open hot water taps to drain and relieve pressure
from the plumbing system. If water continues to flow
after 5 minutes, a plumbing crossover is present and
must be corrected before proceeding.
5. Disconnect inlet and outlet water pipes from the
water heater. Place a small bucket underneath the
water heater to catch residual water remaining inside
the water heater. Save washers for future use.
6. Using an air compressor, blow short bursts of air
(100 PSI Maximum) through the inlet water connection until there is no water coming out of the outlet
water connection of the heater.
7. Reconnect water fittings and return heater to service
when danger of freezing has passed.
HOT
COLD
Fig. 38
28
6 720 608 263
Maintenance and service
5.3
Mineral scale build-up
Periodic descaling may be necessary in areas with high
mineral content in the water. Scale buildup in the heat
exchanger may result in lower flow rates, error codes of
A7 and E9 and boiling sounds in the heat exchanger.
16.Reconnect electrical supply to unit, open water
isolation valves, and return the unit to service.
Descaling using a pump
1. Disconnect electrical supply from the water heater.
2. Shut off the water supply to the water heater using
(installer supplied) shut-off valve.
3. Open hot water taps to drain and relieve pressure
from the plumbing system.
4. Drain water from the unit's heat exchanger by
disconnecting inlet and outlet water connections
from the heater.
5. Connect a line (A) from the outlet of the circulating
pump (installer supplied) to the inlet water fitting on
the water heater.
6. Connect another line (B) to the water outlet fitting on
the water heater. Route the other end of this line into
a descaling reservoir.
7. Using a 3rd line (C) from the descaling reservoir,
connect to the inlet side of circulating pump. Install a
filter on the end of the line in the descaling reservoir.
8. Make sure all connections are "hand tight.".
9. Fill reservoir with descaling solution so both lines
inside are submersed. We recommend straight white
vinegar. If using a commercial descalant, refer to
manufacturer's instructions on dilution with water.
10.Operate the circulating pump.
11.Make sure there are no leaks and the solution is
flowing from the descaling reservoir through the
heater and returning to the reservoir.
12.Run solution through the heater until the solution
returning to the descaling reservoir comes out clear.
(Changing to a fresh solution may be necessary
during this process).
13.Disconnect all lines and drain all solution from heat
exchanger. Properly discard of solution.
14.Position a container below the hot water outlet and
reconnect cold water supply. Open cold water
supply shut-off valve and flush heat exchanger with
clean water.
15.Shut cold water shut-off valve and reconnect hot
water line to the water heater.
Fig. 39
5.4
Adjusting CO2
The CO2 can only be adjusted by a certified gas
technician with a calibrated CO2 analyzer.
Caution: One factor that may affect
CO2 levels is improper gas pressure.
Please see Chapter 3.8 for the
procedure to measure gas pressure
and record your findings below:
Static Gas Pressure:
P1 Operating Pressure:
“ WC
“ WC
The P1 minimum operating gas pressure is 5" WC for
Natural Gas and 11"WC for Propane. Do not proceed
in adjusting CO2 until pressure is at or above these
levels, but not to exceed 14” WC.
A. Once Gas Pressure is adequate
B Turn ON/OFF switch to the OFF (O) position.
B Remove brass flat head screw on the exhaust collar
as seen in Fig. 40.
B Insert CO2 analyzer probe into the measuring port.
The tip of the probe should be in the center of the flue
6 720 608 263
29
Maintenance and service
pipe (approx 1.5" inserted). Avoid air gaps between
probe and measuring port as it can alter readings.
CO2 level
Max CO
level
Nat. Gas
max. input
P1
9.7 ± 0.3 %
min. input
P2
9.5 ± 0.5 %
300 ppm
LP Gas
max. input
P1
10.7 ± 0.3 %
min. input
P2
10.5 ± 0.5 %
300 ppm
* Final reading must be confirmed with the front cover on,
CO2 levels increase when the cover is installed.
Table 9
Fig. 40 Measuring port
1. If P1 CO2 level is off:
B While holding the Program (P) button, turn the ON/
OFF switch to ON (I) position (see Fig. 41). As soon
as ‘188’ flashes on the display, release the Program
button. The display should now read P2. Press
button until “P1” appears on display.
B Loosen yellow painted philips screw (1) and cover
should rotate down (2) revealing a recessed brass
slotted screw. Fig. 42.
B Turning the slotted screw counter clockwise will
raise P1 CO2 levels and clockwise will lower P1
CO2 levels. Adjustments to the slotted screw will
also change P2 CO2 levels.
B After bringing the P1 CO2 readings in range, press
the
button to enter the P2 mode. Verify CO2
readings in P2 mode.
Fig. 41
B. Measuring CO2 (Cover Installed):
B Open all hot water taps to achieve a flow rate of at
least 4 gallons per minute. (1 tub and 2 sinks should
be sufficient).
B Record the CO2 reading in P1 below. (Analyzer
reading may take several minutes to stabilize).
B Press the ‘
’ button until P2 appears. Unit will
ramp down to low fire and the water flow should
decrease.
B Record the CO2 reading in P2 below.
P1 CO2 Reading:
% CO2
P2 CO2 Reading:
% CO2
C. Adjusting CO2 (cover removed):
Note: when making adjustments with the front cover off,
CO2 values will be 0.3 - 0.5% lower than with the front
cover on. Adjust values accordingly to make target numbers in Table 10 when cover is secured.
Compare your readings to those found in Table 10. If
CO2 readings are off, make adjustments as outlined
below.
Fig. 42 Adjusting P1 CO2 level
2. If P2 CO2 level is off:
B Remove yellow painted #40 Torx cover from the front
of the gas valve. (Fig. 43) A plastic #40 Torx screw
will be revealed.
B Turning the plastic #40 Torx screw counter
clockwise will lower P2 CO2 levels and clockwise
will raise P2 CO2 levels.
Note: These screw adjustment are very sensitive and
may take several minutes to stabilize.
Note: P1 adjustment will change the P2 reading. Confirm the P1 value BEFORE adjusting the P2 level.
30
6 720 608 263
Maintenance and service
Fig. 43 Adjusting P2 CO2 level
3. Verify both P1 and P2 CO2 readings are within the
ranges specified in table 10. Repeat steps 1 and 2 as
necesssary until CO2 values are within the specified
ranges.
4. Once CO2 values are within the specified ranges,
verify the CO readings on P1 do not exceed 300ppm
(follow local codes). If values exceed this limit, inspect
vent system and fin coils (Chapter 5.1) for blockage.
D. Returning to Service:
1. Return slotted screw cover to original position.
2. Reinstall Torx cover.
3. Remove CO2 analyzer probe and reinstall flathead
screw with gasket in exhaust collar.
4. Install front cover.
5. Turn ON/OFF switch to the OFF (O) position and
then back to the ON (I) position.
6. Heater is ready for normal operation.
CO2 level
Max CO
level
Nat. Gas
max. input
P1
9.7 ± 0.3 %
min. input
P2
9.5 ± 0.5 %
300 ppm
LP Gas
max. input
P1
10.7 ± 0.3 %
min. input
P2
10.5 ± 0.5 %
300 ppm
* Final reading must be confirmed with the front cover on,
CO2 levels increase when the cover is installed.
Table 10
Final Readings
P2 CO2 Reading:
% CO2
P1 CO2 Reading:
% CO2
6 720 608 263
31
Maintenance and service
5.5
Control board diagnostics
1. Turn on/off switch on water heater to off (O) position.
Diagnostic menu
E
Entry/Exit into sub-modes
0d
Set-point temperature
1d
Inlet water temperature (F)
2d
Outlet water temperature (°F)
3d
Water flow (gallons/min)
4d
Gas type (LP or NG)
5d
Fan speed (Hz)
6d
Burner power (%)
7d
Maximum power (kW)
8d
PWM cycle (signal to fan)
9d
Appliance selection
1F
Most recent error/failure
2F
2nd most recent error
3F
3rd most recent error
4F
4th most recent error
EXAMPLE: to read the flow rate in gallons per minute
while the unit is flowing water, cycle to the '3d' mode
and press the '
' button. A reading of 25 on the
display would indicate the heater is reading a flow rate
of 2.5 gallons/minute.
5F
5th most recent error
6F
6th most recent error
7F
7th most recent error
8F
8th most recent error
6. Once the information is obtained, press the '
'
button again to return to the diagnostic mode menu
and scroll to addition diagnostic information.
9F
9th most recent error
10F
10th most recent error
2. Press and hold the program (
) button while
turning the on/off switch to the on (I) position. The
display will cycle through a startup procedure
including the software version.
3. Release the '
' button when '188' appears on the
display. The display should read 'P2' when the
program button is released. If not, repeat process.
B Press and release the '
' button on the control
panel until the display reads 'P4'. You are now in the
diagnostic mode of the control board.
4. When the display reads 'P4', press and release the
'
' button once again and the display should read
'E'.
B Use the '
to cycle
available.
' and '
through
' button on the control board
different diagnostic modes
5. Once in the selected diagnostic mode of your
choice, press and release the '
' button to display
the diagnostic information.
Table 11
B To exit the diagnostic mode of the heater, use the
'
' or '
' button until the display reads 'E'.
7. Press the '
' button once again and the display
should read P4.
8. Turn the on/off switch off (O) and back on (I) again to
return heater to normal function.
32
6 720 608 263
Troubleshooting
6
Troubleshooting
Warning: If you are unable to perform
the tasks listed below, or need
additional assistance please contact
your original installer/licensed gas
technician.
6.1
Introduction
Many of the questions customers ask regarding
operation of this unit can be answered by following the
troubleshooting steps as outlined below. Visit our web
site at www.boschhotwater.com for more detailed
troubleshooting. For best results, perform each step
before proceeding to the next. The suggested solutions
may require that the cover be taken off. (See Page 5.
Fig. 3).
6.2
Burners do not ignite when hot
water is turned on
1. If the display is blank, verify power to electrical outlet.
(120VAC/60Hz properly grounded circuit required).
Verify that the heater on/off switch is in the on (I)
position.
2. Verify the fuses in the control unit are good.To
access fuses, the control unit must be removed. Go
to www.boschhotwater.com for a detailed service
bulletin on this process. Two spare fuses are located
inside lower access panel of control unit.
3. Make sure cold water inlet connection is plumbed to
the right side of heater when facing unit. See Fig. 25.
4. A minimum of 0.8 gallons per minute (GPM) (3 l/m)
is required to activate the heater. A quart container
should fill in 20 seconds or less to activate heater.
unit's front cover (See Page 5. Fig 3). Check wire
connections between the water valve, control unit
and electrode set. See chapter 9.2 for location of
these parts.
6.3
Water is too hot
1. Selected temperature on the unit is too high. To
lower output temperature, see chapter 4.3.
2. Clean inlet filter screen per chapter 5.1.
3. Inspect the water path for obstructions. Make sure all
showerheads, faucet aerators and whole house
filters are clear of debris.
4. Confirm the heater's gas type coincides with the type
of gas being supplied. See Fig. 2 for location of
rating plate.
5. This model is designed for cold water supply only.
For solar preheated applications, use of the model
125BS is recommended.
6. If the inlet cold water temperature is greater than
70°F due to geographic location avoid restrictive
outlets. Clean all showerheads and faucet aerators. It
may be necessary to upgrade to higher flow rate
fixtures if allowable by local code.
7. In areas where water has a high mineral content,
periodic descaling may necessary. See chapter 5.3
for directions.
8. Ensure that both temperature sensors are making
contact and firmly mounted on their respective cold
and hot water pipes. The hot water sensor should be
located on the horizontal section of the hot water
pipe before it exits the heater. The cold water sensor
is located on the first horizontal section of pipe as the
water comes into the heater.
5. Clean inlet filter screen per chapter 5.1.
6. Inspect the water path for obstructions. Make sure all
showerheads, faucet aerators and whole house
filters are clear of debris.
7. The heater activates when the water flow through the
unit is at or above the required minimum of 0.8 GPM
(3 l/m). A crossover creates back pressure on the
water flowing through the heater. Therefore, a higher
flow rate than normal is needed to force the heater to
activate. To check for a plumbing crossover, shut off
the cold water supply feed to the water heater. Then
open all of the hot water taps served by the heater.
Wait 10 minutes and check for water flow at taps.
There should be no water flowing. Any continuous
flow of water indicates a crossover is present and
must be corrected. Consult a professional plumber
for help in correcting a crossover. Failing single lever
faucets and mixing valves are common causes of
plumbing crossovers.
6.4
Water is not hot enough
1. Selected temperature on the unit is too low. To raise
output temperature, see chapter 4.3.
2. Clean inlet filter screen. See chapter 5.1.
3. Inspect the water path for obstructions. Make sure all
showerheads, faucet aerators and whole house
filters are clear of debris.
4. Confirm the heater's gas type coincides with the type
of gas being supplied. See Fig. 2 for location of
rating plate.
5. Check inlet gas particle screen for blockage at gas
inlet connection on bottom of unit.
6. Verify gas pressure is in accordance with
specifications in chapter 3.8. A gas pressure reading
is needed to proceed further. Contact your original
installer or a local certified gas technician to obtain
this reading.
8. With the ON/OFF switch turned to OFF (O) position
and the power supply cord unplugged, remove the
6 720 608 263
33
Troubleshooting
7. Cold water is mixing into the hot water lines
(plumbing crossover). A plumbing crossover can
unintentionally mix cold water with the hot water
leaving the heater. The end result is a cooler water
temperature than desired. To check for a plumbing
crossover, shut off the cold water supply feed to the
water heater. Then open all of the hot water taps
served by the heater. Wait 10 minutes and check all
taps for water flow. There should be no water
flowing. Any continuous flow of water, small or large,
indicates a crossover and must be corrected. Failing
single lever faucets and mixing valves are common
causes of plumbing crossovers.
8. Ensure that both temperature sensors are making
contact and firmly mounted on their respective cold
and hot water pipes. The hot water sensor should be
located on the horizontal section of the hot water
pipe before it exits the heater. The cold water sensor
is located on the first horizontal section of pipe as the
water comes into the heater.
6.5
Low water flow/pressure
1. Too many hot water applications are being used
simultaneously or too much flow is demanded. The
water heater will effectively support two 2.0-2.5
GPM shower heads simultaneously or multiple sink
applications. Greater draws will result in a water
pressure drop and reduced flow at taps.
2. Ensure that gas pressure is in accordance with
specifications in chapter 3.8. A gas pressure reading
is needed to proceed further. Contact your original
installer or a local certified gas technician to obtain
this reading. If gas pressure is inadequate, the water
heater will close its motorized water valve, reducing
the hot water flow rate in an attempt to reach the
selected output temperature.
3. If selected temperature on the unit is set too high for
the demanded flow rate, the water heater will close
its motorized water valve, reducing the hot water flow
rate in an attempt to reach the selected output
temperature. Lowering the selected temperature will
allow the motorized water valve to open up for
increased water flow rate.
4. Clean inlet filter screen per chapter 5.1.
5. Inspect the water path for obstructions. Make sure all
showerheads, faucet aerators and whole house
filters are clear of debris.
6.6
Hot water temperature fluctuates
at tap
Note: Temperature fluctuations from hot to cold during
use are typically caused by a restriction in the hot water
flow from the tankless heater. This slows the flow within
the tankless heater, decreasing it below the activation
flow rate, which shuts off the burners. The end result is
nothing but cold water coming out of the outlet. Follow
34
each step below before proceeding to the next. After
each step, test the hot water flow to see if it remains
constant without turning cold.
1. Check for restrictions in plumbing outlets, which
could limit hot water flow and may contribute to
heater deactivation. For sinks, remove faucet aerator.
Flush and clean screen and reinstall. For showers,
remove showerhead and flush. If plugged with mineral deposits, clean according to manufacturer’s suggestions or replace shower head. (If showerhead is
wand style/hand held, corrugated tube connecting to
head may be too restrictive. Use a larger tube or
replace with a normal showerhead.)
2. Clean inlet filter screen per chapter 5.2.
3. Check for a plumbing crossover by closing the
installer supplied cold water shut off valve (if none
installed, install before proceeding) and opening all
hot water taps supplied by the heater. Wait 5
minutes and check all taps. The water flow should
come to a complete stop at every tap. Any water
running, even a trickle, is a sign of a plumbing
crossover. Consult a local plumber or service person
for help. This condition must be corrected before the
heater can operate properly.
4. Confirm water pressure is adequate and constant..
Water pressure must stay above 30psi during heater
operation. For installation on a private well system
with the use of a pressure tank, the lowest pressure
range setting recommended is 30-50 psi (2.07-3.45
bar). The use of a pressure reducing/regulating valve
directly after the pressure tank is an effective way to
maintain constant water pressure to the water heater.
Watts brand 25AUB-¾” or N35B-¾” pressure
reducing/regulating valves or equivalent is
suggested.
5. Heater deactivated by temperature balancing valves.
If the outlet water temperature is set too high, the
heater can produce temperatures that are too hot. A
temperature balance shower valve will automatically
mix in cold water to reduce such hot water temperature. In the event of any temperature instability at a fixture using a temperature balancing valve, refer to the
valve manufacturer for instructions on internal adjustment setting. An adjustment should be made to minimize the amount of cold water the valve is adding.
Additionally, the temperature setting on the heater
can be lowered to prevent the temperature balance
valve from mixing in too much cold.
6.7
Noisy burner/heater during
operation
1. Sealed combustion leak. Make sure cover is securely
fastened. Ensure the exhaust vent adaptor is properly
sealed with supplied gasket. Leaky seals create
improper combustion resulting in noise.
6 720 608 263
Troubleshooting
2. Improper venting. Venting that is unsealed, the wrong
material, too big in diameter or too long in run will
result in unstable burner flames and noise. Ensure
venting is correct and in accordance with
specifications in chapter 3.6.
3. Lack of adequate combustion air. Drawing
combustion air from a room area of inadequate size
or improper piping of combustion air from the outside
will result in unstable burner flames and noise.
Ensure adequate combustion air is provided to the
unit in accordance with specifications in Section 3.5
Combustion Air Requirements.
4. Cross contamination. Ensure that intake and exhaust
terminations maintain required clearances stated in
the manual. Cross contamination between intake and
exhaust may cause unstable burner flames and noise.
5. Lack of gas pressure. Inadequate gas pressure will
cause the fuel-to-air mixture (CO2) to be out of
adjustment. This will result in unstable burner flames
and noise. Ensure gas pressure is in accordance with
specifications in Section 3.8 Measuring Gas
Pressure. A gas pressure reading is needed to
proceed further. Contact your original installer or a
local certified gas technician to obtain this reading.
6. Verify proper CO2 readings per chapter 5.4. CO2
adjustments must be done by a certified gas
technician with a calibrated combustion gas
analyzer.
6 720 608 263
35
Troubleshooting
6.8
Error code diagnostics
Part numbers subject to change.
Display
Cause
Solution
A2
Fault in the flue gas limiter (part#
8700400032).
Note: Old style overheat cutoff fuse
(8700400019) has been replaced with this
new limiter.
1. Check for flue gas leakage around the top and
bottom seals of heat exchanger as well as the
viewing window. Look for any noticeable burn marks
or warping of the gaskets. If a leak is detected, seals
will need replacing.
2. Verify that venting meets specifications outlined
in chapter 3.6. Long vent lengths, incorrect venting
material, venting with more than three elbows,
blocked vent or combination venting may cause this
failure. Verify backdraft flapper inside flue gas
collector is not stuck shut.
3. Check flue gas limiter wire connectors for
tightness. Clean with pencil eraser if any corrosion
is evident.
4. Trace wires from flue gas limiter to black
connector. Verify the connection is tight.
5. If limiter is tripped due to overheating, it must cool
down before error will clear on the control board.
A7
Hot water temperature sensor fault
(Temperature below 36°F or above 210°F)
(part# 8700400015)
1. Check red wire connections at the hot water
temperature sensor. Clean terminals with a pencil
eraser. If badly corroded, replace sensor and wire
harness. Verify that sensor is firmly clipped on to the
hot water copper pipe.
2. Sensor may trip if water temperature drops below
36°F. Protect heater from freezing condition as any
damage due to freezing conditions is not covered
under warranty.
3. Clean inlet filter screen per chapter 5.1 and clear
any debris out of showerheads, faucet aerators and
whole house filters.
4. In areas where water has a high mineral content,
periodic descaling may necessary. See chapter 5.3
for directions.
5. Swap sensor with the cold water sensor, keeping
respective wire connections as they are. If the
heater produces an E2 error, replace the sensor.
A9
(Flashing)
Hot water temperature sensor not sensing
expected output temperature.
(part# 8700400015)
1. Check that the sensor is firmly attached to the
horizontal section of the hot water pipe.
2. Clean inlet filter screen per chapter 5.2 and clear
any debris out of showerheads, faucet aerators and
whole house filters.
3. Verify that venting meets specifications outlined
in chapter 3.6. Long vent lengths, incorrect venting
material, venting with more than three elbows,
blocked vent or combination venting may cause this
failure. Verify backdraft flapper inside flue gas
collector is not stuck shut.
4. Check gas pressure per chapter 3.8*. Low gas
pressure may prevent the heater from reaching
desired output temperature.
5. Check supply voltage is 120VAC and is properly
grounded.
6. Possible defective control unit. Call Bosch Water
Heating for further instructions.
Table 12
* By installer or service technician only.
36
6 720 608 263
Troubleshooting
Display
Cause
Solution
C1
Fan rotation too low on startup.
(part# 8707204039)
1. Disconnect power supply cord. Check wire
connections on back side of fan and the two large
wire connectors on the control unit. Removal of
lower access panel on control unit is necessary to
access connectors.
2. Verify that supply voltage is 120VAC and is
properly grounded.
3. Verify that venting meets specifications outlined
in chapter 3.6. Long vent lengths, venting with more
than three elbows, blocked vent or combination
venting may cause this failure. Verify backdraft
flapper inside flue gas collector is not stuck shut.
4. Check gas pressure. See chapter 3.8. Low gas
pressure may cause the fan to change its speed to
meet desired temperature.
5. Possible defective control unit. Call Bosch Water
Heating for further instructions.
C6
Fan rotation too low in operation
(part# 8707204039)
1. Disconnect power supply cord. Check wire
connections on back side of fan and the two large
wire connectors on the control unit. Removal of
lower access panel on control unit is necessary to
access connectors.
2. Check supply voltage is 120VAC and is properly
grounded.
3. Verify that venting meets specifications outlined
in chapter 3.6. Long vent lengths, venting with more
than three elbows, blocked vent or combination
venting may cause this failure. Verify backdraft
flapper inside flue gas collector is not stuck shut.
4. Ensure intake and exhaust terminations maintain
the required clearances stated in the manual ( Fig.
17 and Table 6 on page 17). Cross
contamination between intake and exhaust may
cause the fan to alter its rotational speed.
5. Check gas pressure. See chapter 3.8*. Low gas
pressure may cause the fan to change its speed to
meet desired temperature.
6. Possible defective control unit. Call Bosch Water
C7
No rotational speed sensor from fan.
(part# 8707204039)
1. Disconnect power supply cord. Check wire
connections on back side of fan and the two large
wire connectors on the control unit. Removal of
lower access panel on control unit is necessary to
access connectors.
2. Check supply voltage is 120VAC and is properly
grounded.
3. Possible defective component in fan. Call Bosch
Water Heating for further instructions.
CA
Water flow signal over specified maximum
value.
(part# 8708505016)
1. Disconnect power supply cord and check wire
connections on water valve and the two connectors
on the control board.
2. Excessive water pressure and flow. Ensure water
pressure is less than 150psi and flow rate is less
than 10 gallons per minute.
Table 12
* By installer or service technician only.
6 720 608 263
37
Troubleshooting
Display
Cause
Solution
E1
Over-temperature detected by temperature
sensor on hot water pipe.
(part# 8700400015)
1. This water heater must be supplied with cold
water for domestic hot water only. Do not
recirculate water through this heater or supply with
preheated water.
2. Check that the hot water temperature sensor is
firmly attached to the horizontal section of the hot
water pipe.
3. Check red wire connections at hot water
temperature sensor. Clean terminals with an eraser.
If badly corroded, replace sensor and wire harness.
4. Swap hot water temperature sensor with the cold
water temperature sensor. If the heater produces
an E2 error, replace hot water temperaure sensor.
5. Clean inlet filter screen per chapter 5.2 and clear
any debris out of shower heads, faucet aerators and
whole house filters.
6. In areas where water has a high mineral content,
periodic descaling may necessary. See chapter 5.3
E2
Cold water temperature sensor fault.
(part# 8700400015)
1. Check blue wire connections at cold water
temperature sensor. Clean terminals with an eraser.
If badly corroded, replace sensor and wire harness.
2. Verify that the sensor is firmly attached to the
horizontal section of the cold water pipe.
3. Sensor will trip if it detects temperatures at or
below 36°F. Protect heater from freezing conditions
as any damage resulting from freezing is not
covered under warranty.
4. Swap cold water temperature sensor with the hot
water temperature sensor. If the heater produces an
A7 error, replace cold water temperature sensor.
E9
Temperature limiter (ECO) open circuit
(should reset when cooler temperatures are
detected).
(part# 8707206204)
1. This water heater must be supplied with cold
water for domestic hot water only. Do not
recirculate water through this heater or supply with
preheated water.
2. Disconnect power supply cord and check white
wire connections on ECO (top right of heat
exchanger). Clean terminals with an eraser. If badly
corroded, replace sensor and wire harness.
3. Verify that venting meets specifications outlined
in chapter 3.6. Long vent lengths, venting with more
than three elbows, blocked vent or combination
venting may cause this failure. Verify backdraft
flapper inside flue gas collector is not stuck shut.
4. Clean inlet filter screen per chapter 5.1 and clear
any debris out of shower heads, faucet aerators and
whole house filters.
5. In areas where water has a high mineral content,
periodic descaling may necessary. See chapter 5.3
for directions.
6. Unplug power supply cord to the water heater.
Open a hot water tap for several minutes to allow
cold water to pass through heat exchanger. Close
hot water tap and disconnect lead wires to ECO.
Using a multimeter, check continuity through ECO
Table 12
* By installer or service technician only.
38
6 720 608 263
Troubleshooting
Display
Cause
Solution
EA
No flame ionization detected with water
flow.
(part# 8708107020)
1. Verify that all manual gas shut off valves are open.
2. Verify gas type (See Fig. 2) corresponds with the
type of gas supplied to the heater.
3. Reset error code and open a water tap to cycle
the heater in an effort to purge air from gas line
(especially on new installations). Cycling hot water
tap on and off multiple times may be necessary. If
heater still faults with EA error code, have a licensed
gas technician properly purge air out of the gas line
leading to the water heater.
4. Verify the three yellow wire connections to the set
of electrodes (underside of the burner assembly)
are secure.
5. Verify gas pressure meets specifications outlined
in chapter 3.8*.
6. Verify venting meets specifications outlined in
chapter 3.6. Improper venting may cause premature
failure of the flame sensor rod.
7. Observe inside the viewing window of the heat
exchanger when a hot water tap is opened.
Sparking should be followed by a steady blue flame.
If not, Call Bosch Water Heating with observations.
Readings from above gas pressure test will be
required.
EC
Ionization failure during operation.
(part# 8708107020)
1. Verify gas type (See Fig. 2) corresponds with the
type of gas supplied to the heater.
2. Verify the three yellow wire connections to the set
of electrodes (underside of the burner assembly)
are secure.
3. Verify that venting meets specifications per
chapter 3.6. Improper venting may cause premature
failure of the flame sensor rod.
4. Check gas pressure. See chapter 3.8*.
5. Check and adjust CO2 readings. See
chapter 5.4.
6. Gas valve or flame sensor may be damaged. Call
Bosch Water Heating with observations and results
of previous steps.
E0
Internal hardware/software failure.
(part# 8707207239)
1. Disconnect power supply cord and check the two
wire connectors on the control board.
2. Pushing the wrong combination of buttons on the
control unit can create confusion among the
microprocessors inside. In this case, the error code
should not happen more than once or twice. Turn off
the water heater. Turn water heater back on and
reset error code. Only use the reset button (
) to
reset any error codes.
3. Possible defective control unit call Bosch Water
Heating for further instructions.
Table 12
* By installer or service technician only.
6 720 608 263
39
Troubleshooting
Display
Cause
Solution
F7
Ionization error at standby.
(part# 8708107020)
1. Loose connection to the flame ionization rod.
Verify that the thinner yellow wire leading from the
control unit is securely connected to the set of
electrodes located at the bottom right-hand side of
the heat exchanger.
2. Flame ionization rod or control unit may be
damaged. Contact Bosch Water Heating for further
instruction.
FA
Gas leakage error, gas valve circuit not
closing properly.
(part# 8707021019)
1. Disconnect power supply cord and check wire
connections on gas valve and the two connectors
on the control board.
2. Flow water out of a hot water tap above the
minimum activation point of .8GPM. Measure
voltage at the gas valve wire connector. The
connector should measure 24VDC between the left
pair of wires and 24VDC between the right pair of
wires when the unit is operating. If voltage is not
correct, contact Bosch Water Heating for further
instruction.
3. Gas valve may be defective, contact Bosch
Water Heating for further instruction.
8E
Electronic noise on control unit.
(part# 8707207239)
1. Improper resetting of other error codes. Using the
on/off switch or unplugging the power cord to reset
error codes can interrupt signal between
microprocessors inside control unit and show 8E on
the display. Only use the reset button (
) to reset
any error codes.
2. Possible defective control unit call Bosch Water
Heating for further instructions.
Table 12
* By installer or service technician only.
40
6 720 608 263
Electrical diagram
7
Electrical diagram
Fig. 44 Electrical scheme
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
Intlet water temperature sensor
Ionization sensor
Water flow sensor
Flue gas limiter
Temperature limiter / ECO
Gas valve
Fan
Water valve
AC Plug
Ignition electrode
Display PCB
ON/OFF switch
Fuse T 2.5A
Fuse T 3.15A
Terminal block
Ground post
Outlet water temperature sensor
6 720 608 263
41
2400 E Functional scheme
8
2400 E Functional scheme
Fig. 45 Functional scheme
42
6 720 608 263
Interior components diagram and parts list
9
Interior components diagram and parts list
9.1
Interior components
Fig. 46 Components
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
Cover
On/Off switch
Reset button
LCD display
Program button
Temperature switches
Flue gas collector
Mixer
Heat exchanger
Observation window
Inlet air duct
Control unit
Exhaust fan
Water valve
Gas valve
Fig. 47 Appliance overview
6 720 608 263
43
Interior components diagram and parts list
9.2
Components diagram
Fig. 48 Components Diagram
44
6 720 608 263
Interior components diagram and parts list
9.3
Parts list
Item
Description
Reference
1
Front cover
8 705 421 837
2
Shield
8 705 506 661
3
Heat exchanger
8 705 406 285
4
Heat exchanger top gasket
8 704 701 052
5
Clip
8 716 102 607
6
Heat exchanger bottom gasket
8 704 701 054
7
O-ring
8 700 205 147
8
Temperature sensor
8 700 400 015
9
Washer 1/2"
8 710 103 045
10
Wireform spring
8 714 606 002
11
Air inlet duct
8 705 700 097
12
Water filter
8 700 507 001
13
O-ring
8 700 205 134
14
Water valve with engine
8 708 505 023
15
Main burner
8 708 120 515
16
Fan / Burner gasket
8 704 701 050
17
Set of electrodes
8 708 107 020
18
Exhaust Fan
8 707 204 039
19
Gas / Air Mixer
8 705 700 115
20
Mixer / Fan gasket
8 704 701 059
21
Gas valve washer
8 704 701 062
22
Gas valve
8 707 021 019
23
Gas valve washer
8 700 103 014
24
Remote control (optional accessory)
TSTAT2
25
Control unit
8 707 207 268
26
Ignition cable
8 704 401 220
27
Cables / 24V
8 704 401 214
28
Cables
8 704 401 314
29
Power supply cord
8 704 401 221
30
Flue gas limiter
8 700 400 032
31
Flue gas exhaust accessory
8 705 504 137
32
Combustion air inlet accessory
8 705 504 115
33
Flue gas collector
8 705 700 100
34
Flue gas collector collar
8 705 700 114
35
Cold water pipe
8 700 715 156
36
Hot water pipe
8 700 715 155
37
Attenuator
8 705 700 142
38
Crossover tube
8 700 715 247
39
Overheat sensor (ECO)
8 707 206 204
40
Clip - Heat exchanger
8 701 201 028
42
Gasket Exhaust
8 700 103 710
43
Gasket Set Combustion Chamber
8 704 701 046
44
O-ring air duct
8 700 205 149
45
“BOSCH” decal
8 701 103 124
46
Cold water connection bushing
8 703 305 295
47
Hot water connection bushing
8 703 305 297
48
Mounting bracket
8 708 003 134
Table 13
6 720 608 263
45
Protecting the environment
10
Protecting the environment
Packing
The packing box may be fully recycled as confirmed by
the recycling symbol
.
Components
Many parts in the heater can be fully recycled in the end
of the product life. Contact your city authorities for
information about the disposal of recyclable products.
Saving water resources:
B Make sure you close all the taps after any use. Avoid
leaving the taps dripping. Repair any leaking tap.
B Define the temperature you want, in the appliance or
with the remote control. This way you have the
precise water flow needed (mixing cold water to
regulate temperature will increase the water flow with
consequent waste of water).
46
6 720 608 263
Twelve Year Limited Warranty
11
Twelve Year Limited Warranty
General
Service Labor Costs
Aquastar water heaters are warranted by the
Manufacturer (BOSCH) through BBT North America.
BBT North America (BBTNA) will furnish a replacement
heat exchanger and will furnish a replacement of any
other part which fails in normal use and service within
the applicable periods specified below, in accordance
with the terms of this warranty. The BBTNA
replacement will be warranted for the unexpired portion
of the original warranty. This warranty will be valid only
for water heaters in possession of the original purchaser
as recorded on the warranty card.
This warranty does not cover any labor costs
associated with service, removal or re-installation of
part(s). All such costs must be borne by the Purchaser.
Additionally, this warranty does not cover any labor
costs associated with service, removal or re-installation
of the original water heater or a replaced water heater.
Certain service labor allowances are available to PHCC
member contractors, dependent on prior authorization
by BBTNA.
The Heat Exchanger
If the heat exchanger fails within twelve (12) years after
the original installation and operation, BBTNA will
furnish a replacement heat exchanger. However, if the
water heater is installed in other than a single family
dwelling, this heat exchanger warranty is limited to two
(2) years from date of original installation and operation.
Exceptions
This warranty will not apply:
• 1. to defects or malfunctions resulting from failure to
properly install, operate or maintain the unit in
accordance with the printed instructions provided;
• 2. to damage or abuse resulting from accident,
neglect, flooding, freezing and/or other acts of
nature;
• 3. to damage resulting from operation with either the
flame sensor rod or overheat sensor removed;
• 4. to failure of the heat exchanger resulting from the
operation of the water heater in a corrosive
atmosphere or at water temperatures exceeding the
maximum rating, or if the water heater is not supplied
with potable water;
• 5. to defects or damage cause by any attachment
or modification, including any energy-saving device.
• 6. to damage resulting from scale deposits and/or
highly mineralized / unsoftened water supply
• 7. to damage resulting from supplying the water
heater with pre-heated water.
All Other Parts
If any other part fails within two (2) years after original
installation and operation, BBTNA will furnish a
replacement part free of charge.
Shipping costs
In addition to supplying the replacement part(s),
BBTNA will provide ground service delivery for these
parts. Expedited or upgraded shipping will be charged
to the customer.
6 720 608 263
i
NOTE: the water heater must be free of
damaging scale deposits and not subject
to gas pressures greater than those
shown on the rating plate, which must not
be altered, defaced or removed.
How to Make a Claim
Any claim for warranty parts should be made to your
local dealer, distributor or to BBTNA. If BBTNA, please
contact the Technical Support Department:
BBT NORTH AMERICA
Bosch Group
340 Mad River Park
Waitsfield, VT 05673
Phone 800-642-3111
www.boschhotwater.com
In most cases, the dealer or distributor will be able to
promptly honor your claim and subsequently notify
BBTNA. However, all replacements are made subject to
validation by BBTNA of in-warranty coverage. The
damaged or defective item must be made available in
exchange for the replacement.
Miscellaneous
No one is authorized to make any other warranties on
behalf of BBTNA. It is expressly understood that the
replacement warranty of BBTNA shall be in lieu of any
and all other warranties, express or implied, including
warranties of merchantability or fitness for a particular
use or purpose, and further that BBTNA shall not be
liable for any loss or damage directly or indirectly arising
from the use of the hot water heater, or for any
consequential damages arising from such use
(including damages from water leakage). BBTNA sole
liability with respect to any defect shall be for the
replacement of the defective part(s). Some states do
not allow such limitations and exclusions, so the above
may not apply to you.
This warranty gives specific legal rights. You may also
have other rights which vary from state to state.
47
Replacement Parts available from:
BBT NORTH AMERICA
Bosch Group
Bosch Water Heating
340 Mad River Park
Waitsfield, VT 05673
Phone 800-642-3111
Fax (802) 496-6924
www.boschhotwater.com
techsupport@boschhotwater.com
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BBT Termotecnologia Portugal S.A.
Estrada de Cacia
3801 - 856 Aveiro - PORTUGAL
© 2007 BBT NORTH AMERICA,
Waitsfield, VT all rights reserved